OLED display system and method

Abstract

A method and system control an OLED display to achieve desired color points and brightness levels in an array of pixels in which each pixel includes at least three sub-pixels having different colors and at least one white sub-pixel. The method and system select a plurality of reference points in the pixel content domain with known color points and brightness levels. For each set of three sub-pixels of different colors, the method and system determine the share of each sub-pixel to produce the color point and brightness level of each selected reference point, and select the maximum share determined for each sub-pixel as peak brightness needed from that sub-pixel.

The invention claimed is: 
     
       1. A display device comprising:
 a plurality of pixel circuits, each pixel circuit of the plurality of pixel circuits including at least one sub-pixel circuit comprising:
 a plurality of components including at least one drive transistor, at least one storage element, and at least one light emitting element, each sub-pixel circuit including at least two dedicated sub-pixel portions, each dedicated sub-pixel portion of each sub-pixel circuit including at least one dedicated component of the plurality of components, of the same types and for the same functions, each dedicated sub-pixel portion of said sub-pixel circuit performing differently from each other for at least one range of operation; and 
 
 a controller configured for: 
 controlling the operation of the at least two dedicated sub-pixel portions of the at least one sub-pixel circuit of each pixel circuit based on a range of operation; 
 selecting and driving the at least one sub-pixel circuit of each pixel circuit while activating a first of said at least two dedicated sub-pixel portions and deactivating a second of said at least two dedicated sub-pixel portions for a first range of operation; and 
 selecting and driving the at least one sub-pixel circuit of each pixel circuit while activating the second of said at least two dedicated sub-pixel portions and deactivating the first of said at least two dedicated sub-pixel portions for a second range of operation. 
 
     
     
       2. The display device of  claim 1  wherein said at least one dedicated component of each of said at least two dedicated sub-pixel portions comprises at least one of the at least one driving transistor, the at least one storage element, and the at least one light emitting device. 
     
     
       3. The display device of  claim 1  wherein each of said first and second ranges of operation comprises at least one of a range of environmental conditions and a range of brightness levels. 
     
     
       4. The display device of  claim 1  wherein said first range of operation comprises a first range of brightness levels, and said second range of operation comprises a second range of brightness levels different from the first range of brightness levels. 
     
     
       5. The display device of  claim 4  wherein said first range of brightness levels is less than said second range of brightness levels and wherein the at least one dedicated component of the first of said at least two dedicated sub-pixel portions comprises a drive transistor of a first size and the at least one dedicated component of the second of said at least two dedicated sub-pixel portions comprises a drive transistor of a second size greater than the first size. 
     
     
       6. The display device of  claim 1  wherein each pixel circuit of the plurality of pixels includes a red sub-pixel circuit, a green sub-pixel circuit, and a blue sub-pixel circuit, and said at least one sub-pixel circuit comprises a white sub-pixel circuit. 
     
     
       7. A display device comprising:
 a plurality of pixel circuits, each pixel circuit of the plurality of pixel circuits including at least one sub-pixel circuit comprising:
 a plurality of components including at least one drive transistor, at least one storage element, and at least one light emitting element, each sub-pixel circuit including at least two dedicated sub-pixel portions, each dedicated sub-pixel portion of each sub-pixel circuit including at least one dedicated component of the plurality of components, of the same types and for the same functions, each dedicated sub-pixel portion of said sub-pixel circuit performing differently from each other for at least one range of operation; and 
 
 a controller configured for: 
 controlling the operation of the at least two dedicated sub-pixel portions of the at least one sub-pixel circuit of each pixel circuit based on a range of operation; 
 controlling a first of said at least two dedicated sub-pixel portions while controlling a second of said at least two dedicated sub-pixel portions, the first of said at least two dedicated sub-pixel portions controlled independently from the controlling of the second of said at least two dedicated sub-pixel portions based on the range of operation. 
 
     
     
       8. The display device of  claim 7  wherein said controller is further configured for:
 controlling the first and second of said at least two dedicated sub-pixel portions such that a ratio of currents generated by the first and second of said at least two dedicated sub-pixel portions for driving the at least one light emitting element varies according to varying ranges of operation. 
 
     
     
       9. The display device of  claim 8  wherein the varying ranges of operation comprise varying ranges of brightness levels. 
     
     
       10. A pixel circuit of an array of pixel circuits of a display device, the pixel circuit comprising:
 at least one sub-pixel circuit including a plurality of components including at least one drive transistor, at least one storage element, and at least one light emitting element, each sub-pixel circuit including at least two dedicated sub-pixel portions, each dedicated sub-pixel portion of each sub-pixel circuit including at least one dedicated component of the plurality of components, of the same types and for the same functions, each dedicated sub-pixel portion of said sub-pixel circuit performing differently from each other for at least one range of operation, said at least one range of operation comprises a first range of brightness levels and a second range of brightness levels greater than said first range of brightness levels and wherein the at least one dedicated component of a first of said at least two dedicated sub-pixel portions comprises a drive transistor of a first size and the at least one dedicated component of a second of said at least two dedicated sub-pixel portions comprises a drive transistor of a second size greater than the first size. 
 
     
     
       11. The pixel circuit of  claim 10  wherein said at least one dedicated component of each of said at least two dedicated sub-pixel portions further comprises at least one of the at least one storage element and the at least one light emitting device. 
     
     
       12. The pixel circuit of  claim 10  wherein said at least one range of operation comprises at least one of a range of environmental conditions and a range of brightness levels. 
     
     
       13. The pixel circuit of  claim 10  further comprising a red sub-pixel circuit, a green sub-pixel circuit, and a blue sub-pixel circuit, wherein said at least one sub-pixel comprises a white sub-pixel circuit. 
     
     
       14. A method for controlling a pixel circuit of an array of pixel circuits of a display device, the pixel circuit including at least one sub-pixel circuit including a plurality of components including at least one drive transistor, at least one storage element, and at least one light emitting element, each sub-pixel circuit including at least two dedicated sub-pixel portions, each dedicated sub-pixel portion of each sub-pixel circuit including at least one dedicated component of the plurality of components, of the same types and for the same functions, each dedicated sub-pixel portion of said sub-pixel circuit performing differently from each other for at least one range of operation, said method comprising:
 controlling a first of the at least two dedicated sub-pixel portions for a first range of operation of the at least one range of operation; and 
 controlling a second of the at least two dedicated sub-pixel portions for the first range of operation, the controlling of the second of the at least two dedicated sub-pixel portions independent from the controlling of the first of the at least two dedicated sub-pixel portions for the first range of operation. 
 
     
     
       15. The method of  claim 14  wherein controlling the first of the at least two dedicated sub-pixel portions comprises activating the first of the at least two dedicated sub-pixel portions for the first range of operation and wherein controlling the second of the at least two dedicated sub-pixel portions comprises deactivating the second of the at least two dedicated sub-pixel portions for the first range of operation, the method further comprising:
 deactivating the first of the at least two dedicated sub-pixel portions for a second range of operation of the at least one range of operation and activating the second of the at least two dedicated sub-pixel portions for the second range of operation. 
 
     
     
       16. The method of  claim 15  wherein said first range of operation comprises a first range of brightness levels, and said second range of operation comprises a second range of brightness levels different from the first range of brightness levels. 
     
     
       17. The method of  claim 16  wherein said first range of brightness levels is less than said second range of brightness levels and wherein the at least one dedicated component of the first of the at least two dedicated sub-pixel portions comprises a drive transistor of a first size and the at least one dedicated component of the second of the at least two dedicated sub-pixel portions comprises a drive transistor of a second size greater than the first size. 
     
     
       18. The method of  claim 14  wherein the controlling of the first and second of said at least two dedicated sub-pixel portions is such that a ratio of the currents generated by the first and second of said at least two dedicated sub-pixel portions for driving the at least one light emitting element varies according to varying ranges of operation. 
     
     
       19. The method of  claim 18  wherein the varying ranges of operation comprises varying ranges of brightness levels.